Need suggestions and advice, for installation.
 

Hii, Finally I have decided to use Ubuntu and uninstalling windows completely, I found it very fast OS. But I have some problem, you can say confusions.
have a look on my hardware.
Intel dual core E5700, 4 GB 1333MHZ DDR3 Ram, 80 GB space in C drive(I'll install ubuntu in this drive), and everything is average and working as it should be. Now my confusions are :
1 : Should I use 32bit OS, or 64 bits?
(i have downloaded and tried both,working well, would 64 bit will be a huge improvement in performance?)

2 : Should I make swap area?
(when i have enough ram, then should i make? Not sure what it does.)

3 : Please tell me what my partition structure should be?
(80GB space available, Will install so many applications, need like 20-25GB space for home directory)

4 : and anything else, you can suggest me, for a perfect installation, then please suggest. I'll be thankful.

1. 64 bit if it works. there will be no huge differences, but probably would better.
2. You can make swap, it depends on the usage. Anyway a 1-2GB swap will leave enough space on your drive.
3. use 20-25-30 gb for your home, and another one for the OS. Do not split it into several slices... If you have any special request we need to discuss it. (like database or multimedia server or....)